Three students at a private boarding school needed surgery for serious injuries after suffering electric shocks from overhead cables.
It is believed the boys, who are aged between 13 and 14, sustained serious burn injuries at Millfield School, near Street in Somerset, on Saturday evening.
A school spokesperson said the children remain in hospital in a stable condition following the "isolated accident", and have asked the public to avoid speculation.
Avon and Somerset Police added that a referral was made to the Health and Safety Executive which will lead an investigation into the incident.